[llvm] Add diagnostic help for inline asm operand constraint 'H' (PR #88248)

[Jessica Clarke via llvm-commits]

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@@ -451,14 +475,7 @@ bool SparcAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
         MOReg = RegisterInfo->getMatchingSuperReg(MOReg, SP::sub_even,
                                                   &SP::IntPairRegClass);
         if (!MOReg) {
-          SMLoc Loc;
-          OutContext.reportError(
-              Loc, "Hi part of pair should point to an even-numbered register");
-          OutContext.reportError(
-              Loc, "(note that in some cases it might be necessary to manually "
-                   "bind the input/output registers instead of relying on "
-                   "automatic allocation)");
-          return true;
+          return AsmOperandErrorCode::CONSTRAINT_H_ERROR;
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jrtc27 wrote:

This is for H and L, not just H...

https://github.com/llvm/llvm-project/pull/88248